Cyclic Vomiting Syndrome.

For the last century, empiric therapy has been used to treat the relentless vomiting and resulting dehydration associated with cyclic vomiting syndrome. Despite its unknown pathogenesis, in the last decade, uncontrolled trials of various antimigraine and antiemetic agents have demonstrated rates of efficacy of 40% to 90%. Antimigraine agents are used to prevent or abort episodes, whereas antiemetic agents are used to attenuate symptoms during episodes. A positive family history of migraine headaches renders the patient more likely to respond to antimigraine therapy. In addition to antimigraine therapy, antiemetic sedative/anxiolytic, neuroleptic and gastroinestinal prokinetic agents may be useful.